1 ; Options for the language- and target-independent parts of the compiler.
3 ; Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
4 ; Free Software Foundation, Inc.
6 ; This file is part of GCC.
8 ; GCC is free software; you can redistribute it and/or modify it under
9 ; the terms of the GNU General Public License as published by the Free
10 ; Software Foundation; either version 3, or (at your option) any later
13 ; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 ; WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 ; FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 ; You should have received a copy of the GNU General Public License
19 ; along with GCC; see the file COPYING3. If not see
20 ; <http://www.gnu.org/licenses/>.
22 ; See the GCC internals manual (options.texi) for a description of this file's format.
24 ; Please try to keep this file in ASCII collating order.
35 ; 0 means straightforward implementation of complex divide acceptable.
36 ; 1 means wide ranges of inputs must work for complex divide.
37 ; 2 means C99-like requirements for complex multiply and divide.
39 int flag_complex_method = 1
41 ; Nonzero if subexpressions must be evaluated from left-to-right.
43 int flag_evaluation_order = 0
45 ; Language specific warning pass for unused results.
47 bool flag_warn_unused_result = false
52 ; Nonzero if we should write GIMPLE bytecode for link-time optimization.
56 ; True to warn about any objects definitions whose size is larger
57 ; than N bytes. Also want about function definitions whose returned
58 ; values are larger than N bytes, where N is 'larger_than_size'.
63 HOST_WIDE_INT larger_than_size
65 ; True to warn about any function whose frame size is larger
68 bool warn_frame_larger_than
71 HOST_WIDE_INT frame_larger_than_size
73 ; Nonzero means we should be saving declaration info into a .X file.
75 int flag_gen_aux_info = 0
77 ; Nonzero if we are compiling code for a shared library, zero for
82 ; These two are really VEC(char_p,heap) *.
85 void *flag_instrument_functions_exclude_functions
88 void *flag_instrument_functions_exclude_files
90 ; Generic structs (e.g. templates not explicitly specialized)
91 ; may not have a compilation unit associated with them, and so
92 ; may need to be treated differently from ordinary structs.
94 ; Structs only handled by reference (indirectly), will also usually
95 ; not need as much debugging information.
98 enum debug_struct_file debug_struct_ordinary[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
101 enum debug_struct_file debug_struct_generic[DINFO_USAGE_NUM_ENUMS] = { DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY, DINFO_STRUCT_FILE_ANY }
103 ; True if we should exit after parsing options.
105 bool exit_after_options
107 ; Type(s) of debugging information we are producing (if any). See
108 ; flag-types.h for the definitions of the different possible types of
109 ; debugging information.
111 enum debug_info_type write_symbols = NO_DEBUG
113 ; Level of debugging information we are producing. See flag-types.h
114 ; for the definitions of the different possible levels.
116 enum debug_info_levels debug_info_level = DINFO_LEVEL_NONE
118 ; Nonzero means use GNU-only extensions in the generated symbolic
119 ; debugging information. Currently, this only has an effect when
120 ; write_symbols is set to DBX_DEBUG, XCOFF_DEBUG, or DWARF_DEBUG.
122 bool use_gnu_debug_info_extensions
124 ; Original value of maximum field alignment in bytes, specified via
125 ; -fpack-struct=<value>.
127 unsigned int initial_max_fld_align = TARGET_DEFAULT_PACK_STRUCT
130 enum vect_verbosity_levels user_vect_verbosity_level = MAX_VERBOSITY_LEVEL
132 ; Type of stack check.
134 enum stack_check_type flag_stack_check = NO_STACK_CHECK
136 ; -dA causes debug commentary information to be produced in
137 ; the generated assembly code (to make it more readable). This option
138 ; is generally only of use to those who actually need to read the
139 ; generated assembly code (perhaps while debugging the compiler itself).
140 ; Currently, this switch is only used by dwarf2out.c; however, it is intended
141 ; to be a catchall for printing debug information in the assembler file.
145 ; -dP causes the rtl to be emitted as a comment in assembly.
147 int flag_dump_rtl_in_asm
149 ; Whether -da was passed (used only in handle_common_deferred_options).
151 bool flag_dump_all_passed
153 ; Other flags saying which kinds of debugging dump have been requested.
156 int rtl_dump_and_exit
159 int flag_print_asm_name
162 enum graph_dump_types graph_dump_format = no_graph
164 ; Name of top-level original source file (what was input to cpp).
165 ; This comes from the #-command at the beginning of the actual input.
166 ; If there isn't any there, then this is the cc1 input file name.
168 const char *main_input_filename
170 ; Pointer to base name in main_input_filename, with directories and a
171 ; single final extension removed, and the length of this base
175 const char *main_input_basename
178 int main_input_baselength
180 ; Which options have been printed by --help.
184 ; Which enums have been printed by --help. 0 = not printed, no
185 ; relevant options seen, 1 = relevant option seen, not yet printed, 2
188 char *help_enum_printed
190 ; The number of columns for --help output.
192 unsigned int help_columns
194 ; Whether this options structure has been through finish_options
196 bool flag_opts_finished
208 Driver Alias(coverage)
214 Common Separate Alias(d)
217 Common Joined Alias(d)
220 Common Separate Alias(dumpbase)
223 Common Separate Alias(dumpdir)
226 Driver Separate Alias(e)
229 Driver Joined Alias(e)
232 Common Warning Alias(Wextra)
235 Driver Separate Alias(Xassembler)
238 Driver JoinedOrMissing Alias(Xassembler)
241 Driver Separate Alias(Xlinker)
244 Driver JoinedOrMissing Alias(Xlinker)
247 Driver Separate Alias(u)
250 Driver Joined Alias(u)
253 Common Driver Var(help_flag)
254 Display this information
257 Common Driver Report Joined
258 --help=<class> Display descriptions of a specific class of options. <class> is one or more of optimizers, target, warnings, undocumented, params
261 Driver Separate Alias(x)
264 Driver Joined Alias(x)
267 Driver Separate Alias(L)
270 Driver Joined Alias(L)
272 -no-canonical-prefixes
273 Driver Alias(no-canonical-prefixes)
275 -no-standard-libraries
276 Driver Alias(nostdlib)
285 Common Driver Separate Alias(o) MissingArgError(missing filename after %qs)
288 Common Driver Joined Alias(o) MissingArgError(missing filename after %qs)
291 Driver Alias(pass-exit-codes)
294 Common Alias(pedantic)
297 Common Alias(pedantic-errors)
306 Driver Separate Alias(B)
309 Driver JoinedOrMissing Alias(B)
315 Driver Separate Alias(print-file-name=)
318 Driver JoinedOrMissing Alias(print-file-name=)
320 -print-libgcc-file-name
321 Driver Alias(print-libgcc-file-name)
323 -print-multi-directory
324 Driver Alias(print-multi-directory)
327 Driver Alias(print-multi-lib)
329 -print-multi-os-directory
330 Driver Alias(print-multi-os-directory)
333 Driver Separate Alias(print-prog-name=)
336 Driver JoinedOrMissing Alias(print-prog-name=)
339 Driver Alias(print-search-dirs)
342 Driver Alias(print-sysroot)
344 -print-sysroot-headers-suffix
345 Driver Alias(print-sysroot-headers-suffix)
351 Driver Alias(save-temps)
357 Driver Separate Alias(specs=)
360 Driver Joined Alias(specs=)
366 Driver Alias(symbolic)
370 Alias for --help=target
378 ;; The driver used to convert options such as --help into forms such
379 ;; as -fhelp; the following four entries are for compatibility with
380 ;; any direct uses of those (undocumented) -f forms
382 Common Driver Alias(-help)
385 Common Driver Joined Alias(-help=)
388 Common Driver Alias(-target-help)
391 Common Driver Alias(-version)
395 --param <param>=<value> Set parameter <param> to value. See below for a complete list of parameters
398 Common Joined Alias(-param)
401 Driver Separate Alias(-sysroot=)
404 Driver JoinedOrMissing
410 Driver Joined Separate
416 Driver Joined Separate
422 Common JoinedOrMissing Optimization
423 -O<number> Set optimization level to <number>
427 Optimize for space rather than speed
431 Optimize for speed disregarding exact standards compliance
443 Driver Joined Separate
449 Driver Joined Separate
461 Common RejectNegative Warning Alias(Wextra)
462 This switch is deprecated; use -Wextra instead
465 Driver JoinedOrMissing
468 Driver JoinedOrMissing
471 Driver JoinedOrMissing
474 Common Var(warn_aggregate_return) Warning
475 Warn about returning structures, unions or arrays
478 Common Var(warn_array_bounds) Warning
479 Warn if an array is accessed out of bounds
482 Common Var(warn_attributes) Init(1) Warning
483 Warn about inappropriate attribute usage
486 Common Var(warn_cast_align) Warning
487 Warn about pointer casts which increase alignment
490 Common Var(warn_cpp) Init(1) Warning
491 Warn when a #warning directive is encountered
493 Wdeprecated-declarations
494 Common Var(warn_deprecated_decl) Init(1) Warning
495 Warn about uses of __attribute__((deprecated)) declarations
497 Wdisabled-optimization
498 Common Var(warn_disabled_optimization) Warning
499 Warn when an optimization pass is disabled
502 Common Var(warnings_are_errors)
503 Treat all warnings as errors
507 Treat specified warning as error
510 Common Var(extra_warnings) Warning
511 Print extra (possibly unwanted) warnings
514 Common Var(flag_fatal_errors)
515 Exit on the first error occurred
518 Common RejectNegative Joined UInteger
519 -Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes
522 Common Var(warn_inline) Warning
523 Warn when an inlined function cannot be inlined
526 Common RejectNegative Joined Warning Undocumented Alias(Wlarger-than=)
529 Common RejectNegative Joined UInteger Warning
530 -Wlarger-than=<number> Warn if an object is larger than <number> bytes
532 Wunsafe-loop-optimizations
533 Common Var(warn_unsafe_loop_optimizations) Warning
534 Warn if the loop cannot be optimized due to nontrivial assumptions.
537 Common Var(warn_missing_noreturn) Warning
538 Warn about functions which might be candidates for __attribute__((noreturn))
541 Common Var(warn_mudflap) Init(1) Warning
542 Warn about constructs not instrumented by -fmudflap
545 Common Var(warn_overflow) Init(1) Warning
546 Warn about overflow in arithmetic expressions
549 Common Var(warn_packed) Warning
550 Warn when the packed attribute has no effect on struct layout
553 Common Var(warn_padded) Warning
554 Warn when padding is required to align structure members
557 Common Var(warn_shadow) Warning
558 Warn when one local variable shadows another
561 Common Var(warn_stack_protect) Warning
562 Warn when not issuing stack smashing protection for some reason
566 Warn about code which might break strict aliasing rules
569 Common Joined RejectNegative UInteger Var(warn_strict_aliasing) Init(-1) Warning
570 Warn about code which might break strict aliasing rules
574 Warn about optimizations that assume that signed overflow is undefined
577 Common Joined RejectNegative UInteger Var(warn_strict_overflow) Init(-1) Warning
578 Warn about optimizations that assume that signed overflow is undefined
580 Wsuggest-attribute=const
581 Common Var(warn_suggest_attribute_const) Warning
582 Warn about functions which might be candidates for __attribute__((const))
584 Wsuggest-attribute=pure
585 Common Var(warn_suggest_attribute_pure) Warning
586 Warn about functions which might be candidates for __attribute__((pure))
588 Wsuggest-attribute=noreturn
589 Common Var(warn_suggest_attribute_noreturn) Warning
590 Warn about functions which might be candidates for __attribute__((noreturn))
593 Common Var(warn_switch) Warning
594 Warn about enumerated switches, with no default, missing a case
597 Common Var(warn_switch_default) Warning
598 Warn about enumerated switches missing a \"default:\" statement
601 Common Var(warn_switch_enum) Warning
602 Warn about all enumerated switches missing a specific case
605 Common Var(warn_system_headers) Warning
606 Do not suppress warnings from system headers
609 Common Var(warn_trampolines) Warning
610 Warn whenever a trampoline is generated
613 Common Var(warn_type_limits) Init(-1) Warning
614 Warn if a comparison is always true or always false due to the limited range of the data type
617 Common Var(warn_uninitialized) Init(-1) Warning
618 Warn about uninitialized automatic variables
622 Does nothing. Preserved for backward compatibility.
625 Common Var(warn_unused) Init(0) Warning
626 Enable all -Wunused- warnings
628 Wunused-but-set-parameter
629 Common Var(warn_unused_but_set_parameter) Init(-1) Warning
630 Warn when a function parameter is only set, otherwise unused
632 Wunused-but-set-variable
633 Common Var(warn_unused_but_set_variable) Init(-1) Warning
634 Warn when a variable is only set, otherwise unused
637 Common Var(warn_unused_function) Init(-1) Warning
638 Warn when a function is unused
641 Common Var(warn_unused_label) Init(-1) Warning
642 Warn when a label is unused
645 Common Var(warn_unused_parameter) Init(-1) Warning
646 Warn when a function parameter is unused
649 Common Var(warn_unused_value) Init(-1) Warning
650 Warn when an expression value is unused
653 Common Var(warn_unused_variable) Init(-1) Warning
654 Warn when a variable is unused
657 Common Var(warn_coverage_mismatch) Init(1) Warning
658 Warn in case profiles in -fprofile-use do not match
673 Common Separate Var(aux_info_file_name)
674 -aux-info <file> Emit declaration information into <file>
677 Common Joined Alias(aux-info)
680 Common Separate RejectDriver Var(aux_base_name)
683 Common Separate RejectDriver
693 -d<letters> Enable dumps from specific passes of the compiler
696 Common Separate Var(dump_base_name)
697 -dumpbase <file> Set the file basename to be used for dumps
700 Common Separate Var(dump_dir_name)
701 -dumpdir <dir> Set the directory name to be used for dumps
713 Driver Joined Separate
715 ; The version of the C++ ABI in use. The following values are allowed:
717 ; 0: The version of the ABI believed most conformant with the C++ ABI
718 ; specification. This ABI may change as bugs are discovered and fixed.
719 ; Therefore, 0 will not necessarily indicate the same ABI in different
722 ; 1: The version of the ABI first used in G++ 3.2.
724 ; 2: The version of the ABI first used in G++ 3.4 (and current default).
726 ; 3: The version of the ABI that fixes the missing underscore
727 ; in template non-type arguments of pointer type.
729 ; 4: The version of the ABI that introduces unambiguous mangling of
732 ; Additional positive integers will be assigned as new versions of
733 ; the ABI become the default version of the ABI.
735 Common Joined RejectNegative UInteger Var(flag_abi_version) Init(2)
738 Common Report Var(align_functions,0) Optimization UInteger
739 Align the start of functions
742 Common RejectNegative Joined UInteger Var(align_functions)
745 Common Report Var(align_jumps,0) Optimization UInteger
746 Align labels which are only reached by jumping
749 Common RejectNegative Joined UInteger Var(align_jumps)
752 Common Report Var(align_labels,0) Optimization UInteger
756 Common RejectNegative Joined UInteger Var(align_labels)
759 Common Report Var(align_loops,0) Optimization UInteger
760 Align the start of loops
763 Common RejectNegative Joined UInteger Var(align_loops)
767 Does nothing. Preserved for backward compatibility.
771 Does nothing. Preserved for backward compatibility.
773 fargument-noalias-global
775 Does nothing. Preserved for backward compatibility.
777 fargument-noalias-anything
779 Does nothing. Preserved for backward compatibility.
781 fasynchronous-unwind-tables
782 Common Report Var(flag_asynchronous_unwind_tables) Optimization
783 Generate unwind tables that are exact at each instruction boundary
786 Common Report Var(flag_auto_inc_dec) Init(1)
787 Generate auto-inc/dec instructions
789 ; -fcheck-bounds causes gcc to generate array bounds checks.
790 ; For C, C++ and ObjC: defaults off.
791 ; For Java: defaults to on.
792 ; For Fortran: defaults to off.
794 Common Report Var(flag_bounds_check)
795 Generate code to check bounds before indexing arrays
798 Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
799 Replace add, compare, branch with branch on count register
801 fbranch-probabilities
802 Common Report Var(flag_branch_probabilities) Optimization
803 Use profiling information for branch probabilities
805 fbranch-target-load-optimize
806 Common Report Var(flag_branch_target_load_optimize) Optimization
807 Perform branch target load optimization before prologue / epilogue threading
809 fbranch-target-load-optimize2
810 Common Report Var(flag_branch_target_load_optimize2) Optimization
811 Perform branch target load optimization after prologue / epilogue threading
814 Common Report Var(flag_btr_bb_exclusive) Optimization
815 Restrict target load migration not to re-use registers in any basic block
818 Common Joined RejectNegative Var(common_deferred_options) Defer
819 -fcall-saved-<register> Mark <register> as being preserved across functions
822 Common Joined RejectNegative Var(common_deferred_options) Defer
823 -fcall-used-<register> Mark <register> as being corrupted by function calls
825 ; Nonzero for -fcaller-saves: allocate values in regs that need to
826 ; be saved across function calls, if that produces overall better code.
827 ; Optional now, so people can test it.
829 Common Report Var(flag_caller_saves) Optimization
830 Save registers around function calls
833 Common Report Var(flag_check_data_deps)
834 Compare the results of several data dependence analyzers.
836 fcombine-stack-adjustments
837 Common Report Var(flag_combine_stack_adjustments) Optimization
838 Looks for opportunities to reduce stack adjustments and stack references.
841 Common Report Var(flag_no_common,0) Optimization
842 Do not put uninitialized globals in the common section
846 ; Converted by the driver to -fcompare-debug= options.
849 Common Driver JoinedOrMissing RejectNegative Var(flag_compare_debug_opt)
850 -fcompare-debug[=<opts>] Compile with and without e.g. -gtoggle, and compare the final-insns dump
852 fcompare-debug-second
853 Common Driver RejectNegative Var(flag_compare_debug)
854 Run only the second compilation of -fcompare-debug
857 Common Var(flag_conserve_stack) Optimization
858 Do not perform optimizations increasing noticeably stack usage
861 Common Report Var(flag_cprop_registers) Optimization
862 Perform a register copy-propagation optimization pass
865 Common Report Var(flag_crossjumping) Optimization
866 Perform cross-jumping optimization
869 Common Report Var(flag_cse_follow_jumps) Optimization
870 When running CSE, follow jumps to their targets
874 Does nothing. Preserved for backward compatibility.
877 Common Report Var(flag_cx_limited_range) Optimization
878 Omit range reduction step when performing complex division
881 Common Report Var(flag_cx_fortran_rules) Optimization
882 Complex multiplication and division follow Fortran rules
885 Common Report Var(flag_data_sections) Optimization
886 Place data items into their own section
889 Common Report Var(common_deferred_options) Defer
890 List all available debugging counters with their limits and counts.
893 Common RejectNegative Joined Var(common_deferred_options) Defer
894 -fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...] Set the debug counter limit.
897 Common Joined RejectNegative Var(common_deferred_options) Defer
898 Map one directory name to another in debug information
900 ; Nonzero for -fdefer-pop: don't pop args after each function call
901 ; instead save them up to pop many calls' args with one insns.
903 Common Report Var(flag_defer_pop) Optimization
904 Defer popping functions args from stack until later
907 Common Report Var(flag_delayed_branch) Optimization
908 Attempt to fill delay slots of branch instructions
910 fdelete-null-pointer-checks
911 Common Report Var(flag_delete_null_pointer_checks) Init(1) Optimization
912 Delete useless null pointer checks
914 fdiagnostics-show-location=
915 Common Joined RejectNegative Enum(diagnostic_prefixing_rule)
916 -fdiagnostics-show-location=[once|every-line] How often to emit source location at the beginning of line-wrapped diagnostics
918 ; Required for these enum values.
923 Name(diagnostic_prefixing_rule) Type(int)
926 Enum(diagnostic_prefixing_rule) String(once) Value(DIAGNOSTICS_SHOW_PREFIX_ONCE)
929 Enum(diagnostic_prefixing_rule) String(every-line) Value(DIAGNOSTICS_SHOW_PREFIX_EVERY_LINE)
931 fdiagnostics-show-option
932 Common Var(flag_diagnostics_show_option) Init(1)
933 Amend appropriate diagnostic messages with the command line option that controls them
936 Common Joined RejectNegative Var(common_deferred_options) Defer
937 -fdump-<type> Dump various compiler internals to a file
940 Driver RejectNegative
943 Common RejectNegative Joined Var(flag_dump_final_insns)
944 -fdump-final-insns=filename Dump to filename the insns at the end of translation
947 Common RejectNegative Joined Var(flag_dump_go_spec)
948 -fdump-go-spec=filename Write all declarations to file as Go code
951 Common Report Var(flag_dump_noaddr)
952 Suppress output of addresses in debugging dumps
955 Common Report Var(flag_dump_unnumbered)
956 Suppress output of instruction numbers, line number notes and addresses in debugging dumps
958 fdump-unnumbered-links
959 Common Report Var(flag_dump_unnumbered_links)
960 Suppress output of previous and next insn numbers in debugging dumps
963 Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
964 Enable CFI tables via GAS assembler directives.
967 Common Report Var(flag_early_inlining) Init(1) Optimization
968 Perform early inlining
970 feliminate-dwarf2-dups
971 Common Report Var(flag_eliminate_dwarf2_dups)
972 Perform DWARF2 duplicate elimination
975 Common Report Var(flag_ipa_sra) Init(0) Optimization
976 Perform interprocedural reduction of aggregates
978 feliminate-unused-debug-symbols
979 Common Report Var(flag_debug_only_used_symbols)
980 Perform unused type elimination in debug info
982 feliminate-unused-debug-types
983 Common Report Var(flag_eliminate_unused_debug_types) Init(1)
984 Perform unused type elimination in debug info
986 femit-class-debug-always
987 Common Report Var(flag_emit_class_debug_always) Init(0)
988 Do not suppress C++ class debug information.
991 Common Report Var(flag_enable_icf_debug)
992 Generate debug information to support Identical Code Folding (ICF)
995 Common Report Var(flag_exceptions) Optimization
996 Enable exception handling
998 fexpensive-optimizations
999 Common Report Var(flag_expensive_optimizations) Optimization
1000 Perform a number of minor, expensive optimizations
1003 Common Joined RejectNegative Enum(excess_precision) Var(flag_excess_precision_cmdline) Init(EXCESS_PRECISION_DEFAULT)
1004 -fexcess-precision=[fast|standard] Specify handling of excess floating-point precision
1007 Name(excess_precision) Type(enum excess_precision) UnknownError(unknown excess precision style %qs)
1010 Enum(excess_precision) String(fast) Value(EXCESS_PRECISION_FAST)
1013 Enum(excess_precision) String(standard) Value(EXCESS_PRECISION_STANDARD)
1019 Common Report Var(flag_finite_math_only) Optimization
1020 Assume no NaNs or infinities are generated
1023 Common Joined RejectNegative Var(common_deferred_options) Defer
1024 -ffixed-<register> Mark <register> as being unavailable to the compiler
1027 Common Report Var(flag_float_store) Optimization
1028 Don't allocate floats and doubles in extended-precision registers
1032 Does nothing. Preserved for backward compatibility.
1035 Common Report Var(flag_forward_propagate) Optimization
1036 Perform a forward propagation pass on RTL
1039 Common Joined RejectNegative Enum(fp_contract_mode) Var(flag_fp_contract_mode) Init(FP_CONTRACT_FAST)
1040 -ffp-contract=[off|on|fast] Perform floating-point expression contraction.
1043 Name(fp_contract_mode) Type(enum fp_contract_mode) UnknownError(unknown floating point contraction style %qs)
1046 Enum(fp_contract_mode) String(off) Value(FP_CONTRACT_OFF)
1048 ; Not implemented, fall back to conservative FP_CONTRACT_OFF.
1050 Enum(fp_contract_mode) String(on) Value(FP_CONTRACT_OFF)
1053 Enum(fp_contract_mode) String(fast) Value(FP_CONTRACT_FAST)
1055 ; Nonzero means don't put addresses of constant functions in registers.
1056 ; Used for compiling the Unix kernel, where strange substitutions are
1057 ; done on the assembly output.
1059 Common Report Var(flag_no_function_cse,0)
1060 Allow function addresses to be held in registers
1063 Common Report Var(flag_function_sections)
1064 Place each function into its own section
1067 Common Report Var(flag_gcse) Optimization
1068 Perform global common subexpression elimination
1071 Common Report Var(flag_gcse_lm) Init(1) Optimization
1072 Perform enhanced load motion during global common subexpression elimination
1075 Common Report Var(flag_gcse_sm) Init(0) Optimization
1076 Perform store motion after global common subexpression elimination
1079 Common Report Var(flag_gcse_las) Init(0) Optimization
1080 Perform redundant load after store elimination in global common subexpression
1084 Common Report Var(flag_gcse_after_reload) Optimization
1085 Perform global common subexpression elimination after register allocation
1088 ; This option is not documented yet as its semantics will change.
1090 Common Report Var(flag_graphite)
1091 Enable in and out of Graphite representation
1094 Common Report Var(flag_graphite_identity) Optimization
1095 Enable Graphite Identity transformation
1097 floop-parallelize-all
1098 Common Report Var(flag_loop_parallelize_all) Optimization
1099 Mark all loops as parallel
1102 Common Report Var(flag_loop_strip_mine) Optimization
1103 Enable Loop Strip Mining transformation
1106 Common Report Var(flag_loop_interchange) Optimization
1107 Enable Loop Interchange transformation
1110 Common Report Var(flag_loop_block) Optimization
1111 Enable Loop Blocking transformation
1114 Common Report Var(flag_loop_flatten) Optimization
1115 Enable Loop Flattening transformation
1117 fstrict-volatile-bitfields
1118 Common Report Var(flag_strict_volatile_bitfields) Init(-1)
1119 Force bitfield accesses to match their type width
1121 fguess-branch-probability
1122 Common Report Var(flag_guess_branch_prob) Optimization
1123 Enable guessing of branch probabilities
1125 ; Nonzero means ignore `#ident' directives. 0 means handle them.
1126 ; Generate position-independent code for executables if possible
1127 ; On SVR4 targets, it also controls whether or not to emit a
1128 ; string identifying the compiler.
1130 Common Report Var(flag_no_ident,0)
1131 Process #ident directives
1134 Common Report Var(flag_if_conversion) Optimization
1135 Perform conversion of conditional jumps to branchless equivalents
1138 Common Report Var(flag_if_conversion2) Optimization
1139 Perform conversion of conditional jumps to conditional execution
1141 ftree-loop-if-convert
1142 Common Report Var(flag_tree_loop_if_convert) Init(-1) Optimization
1143 Convert conditional jumps in innermost loops to branchless equivalents
1145 ftree-loop-if-convert-stores
1146 Common Report Var(flag_tree_loop_if_convert_stores) Optimization
1147 Also if-convert conditional jumps containing memory writes
1149 ; -finhibit-size-directive inhibits output of .size for ELF.
1150 ; This is used only for compiling crtstuff.c,
1151 ; and it may be extended to other effects
1152 ; needed for crtstuff.c on other systems.
1153 finhibit-size-directive
1154 Common Report Var(flag_inhibit_size_directive)
1155 Do not generate .size directives
1158 Common Report Var(flag_indirect_inlining)
1159 Perform indirect inlining
1161 ; Nonzero means that functions declared `inline' will be treated
1162 ; as `static'. Prevents generation of zillions of copies of unused
1163 ; static inline functions; instead, `inlines' are written out
1164 ; only when actually used. Used in conjunction with -g. Also
1165 ; does the right thing with #pragma interface.
1167 Common Report Var(flag_no_inline,0) Init(0)
1168 Pay attention to the \"inline\" keyword
1170 finline-small-functions
1171 Common Report Var(flag_inline_small_functions) Optimization
1172 Integrate simple functions into their callers when code size is known to not growth
1175 Common Report Var(flag_inline_functions) Optimization
1176 Integrate simple functions into their callers
1178 finline-functions-called-once
1179 Common Report Var(flag_inline_functions_called_once) Init(1) Optimization
1180 Integrate functions called once into their callers
1183 Common RejectNegative Joined Alias(finline-limit=)
1186 Common RejectNegative Joined UInteger
1187 -finline-limit=<number> Limit the size of inlined functions to <number>
1189 finstrument-functions
1190 Common Report Var(flag_instrument_function_entry_exit)
1191 Instrument function entry and exit with profiling calls
1193 finstrument-functions-exclude-function-list=
1194 Common RejectNegative Joined
1195 -finstrument-functions-exclude-function-list=name,... Do not instrument listed functions
1197 finstrument-functions-exclude-file-list=
1198 Common RejectNegative Joined
1199 -finstrument-functions-exclude-file-list=filename,... Do not instrument functions listed in files
1202 Common Report Var(flag_ipa_cp) Optimization
1203 Perform Interprocedural constant propagation
1206 Common Report Var(flag_ipa_cp_clone) Optimization
1207 Perform cloning to make Interprocedural constant propagation stronger
1210 Common Report Var(flag_ipa_profile) Init(0) Optimization
1211 Perform interprocedural profile propagation
1214 Common Report Var(flag_ipa_pta) Init(0) Optimization
1215 Perform interprocedural points-to analysis
1218 Common Report Var(flag_ipa_pure_const) Init(0) Optimization
1219 Discover pure and const functions
1222 Common Report Var(flag_ipa_reference) Init(0) Optimization
1223 Discover readonly and non addressable static variables
1226 Common Report Var(flag_ipa_matrix_reorg) Optimization
1227 Perform matrix layout flattening and transposing based
1228 on profiling information.
1231 Common Report Var(flag_ipa_struct_reorg)
1232 Perform structure layout optimizations based
1233 on profiling information.
1236 Common Joined RejectNegative Enum(ira_algorithm) Var(flag_ira_algorithm) Init(IRA_ALGORITHM_CB)
1237 -fira-algorithm=[CB|priority] Set the used IRA algorithm
1240 Name(ira_algorithm) Type(enum ira_algorithm) UnknownError(unknown IRA algorithm %qs)
1243 Enum(ira_algorithm) String(CB) Value(IRA_ALGORITHM_CB)
1246 Enum(ira_algorithm) String(priority) Value(IRA_ALGORITHM_PRIORITY)
1249 Common Joined RejectNegative Enum(ira_region) Var(flag_ira_region) Init(IRA_REGION_MIXED)
1250 -fira-region=[one|all|mixed] Set regions for IRA
1253 Name(ira_region) Type(enum ira_region) UnknownError(unknown IRA region %qs)
1256 Enum(ira_region) String(one) Value(IRA_REGION_ONE)
1259 Enum(ira_region) String(all) Value(IRA_REGION_ALL)
1262 Enum(ira_region) String(mixed) Value(IRA_REGION_MIXED)
1265 Common Report Var(flag_ira_loop_pressure)
1266 Use IRA based register pressure calculation
1267 in RTL loop optimizations.
1269 fira-share-save-slots
1270 Common Report Var(flag_ira_share_save_slots) Init(1)
1271 Share slots for saving different hard registers.
1273 fira-share-spill-slots
1274 Common Report Var(flag_ira_share_spill_slots) Init(1)
1275 Share stack slots for spilled pseudo-registers.
1278 Common RejectNegative Joined UInteger Var(flag_ira_verbose) Init(5)
1279 -fira-verbose=<number> Control IRA's level of diagnostic messages.
1282 Common Report Var(flag_ivopts) Init(1) Optimization
1283 Optimize induction variables on trees
1286 Common Var(flag_jump_tables) Init(1) Optimization
1287 Use jump tables for sufficiently large switch statements
1289 fkeep-inline-functions
1290 Common Report Var(flag_keep_inline_functions)
1291 Generate code for functions even if they are fully inlined
1294 Common Report Var(flag_keep_static_consts) Init(1)
1295 Emit static const variables even if they are not used
1298 Common Report Var(flag_leading_underscore) Init(-1)
1299 Give external symbols a leading underscore
1303 Does nothing. Preserved for backward compatibility.
1307 Enable link-time optimization.
1310 Common RejectNegative Joined Var(flag_lto)
1311 Link-time optimization with number of parallel jobs or jobserver.
1314 Common Var(flag_lto_partition_1to1)
1315 Partition functions and vars at linktime based on object files they originate from
1317 flto-partition=balanced
1318 Common Var(flag_lto_partition_balanced)
1319 Partition functions and vars at linktime into approximately same sized buckets
1322 Common Var(flag_lto_partition_none)
1323 Disable partioning and streaming
1325 ; The initial value of -1 comes from Z_DEFAULT_COMPRESSION in zlib.h.
1326 flto-compression-level=
1327 Common Joined RejectNegative UInteger Var(flag_lto_compression_level) Init(-1)
1328 -flto-compression-level=<number> Use zlib compression level <number> for IL
1331 Common Report Var(flag_lto_report) Init(0) Optimization
1332 Report various link-time optimization statistics
1335 Common Report Var(flag_errno_math) Init(1) Optimization
1336 Set errno after built-in math functions
1339 Common Joined RejectNegative UInteger Var(flag_max_errors)
1340 -fmax-errors=<number> Maximum number of errors to report
1343 Common Report Var(mem_report)
1344 Report on permanent memory allocation
1346 ; This will attempt to merge constant section constants, if 1 only
1347 ; string constants and constants from constant pool, if 2 also constant
1349 fmerge-all-constants
1350 Common Report Var(flag_merge_constants,2) Init(1) Optimization
1351 Attempt to merge identical constants and constant variables
1354 Common Report Var(flag_merge_constants,1) Optimization
1355 Attempt to merge identical constants across compilation units
1357 fmerge-debug-strings
1358 Common Report Var(flag_merge_debug_strings) Init(1)
1359 Attempt to merge identical debug strings across compilation units
1362 Common RejectNegative Joined UInteger
1363 -fmessage-length=<number> Limit diagnostics to <number> characters per line. 0 suppresses line-wrapping
1366 Common Report Var(flag_modulo_sched) Optimization
1367 Perform SMS based modulo scheduling before the first scheduling pass
1369 fmodulo-sched-allow-regmoves
1370 Common Report Var(flag_modulo_sched_allow_regmoves)
1371 Perform SMS based modulo scheduling with register moves allowed
1373 fmove-loop-invariants
1374 Common Report Var(flag_move_loop_invariants) Init(1) Optimization
1375 Move loop invariant computations out of loops
1378 Common RejectNegative Report Var(flag_mudflap)
1379 Add mudflap bounds-checking instrumentation for single-threaded program
1382 Common RejectNegative Report Var(flag_mudflap,2)
1383 Add mudflap bounds-checking instrumentation for multi-threaded program
1386 Common RejectNegative Report Var(flag_mudflap_ignore_reads)
1387 Ignore read operations when inserting mudflap instrumentation
1390 Common Var(flag_dce) Init(1) Optimization
1391 Use the RTL dead code elimination pass
1394 Common Var(flag_dse) Init(1) Optimization
1395 Use the RTL dead store elimination pass
1397 freschedule-modulo-scheduled-loops
1398 Common Report Var(flag_resched_modulo_sched) Optimization
1399 Enable/Disable the traditional scheduling in loops that already passed modulo scheduling
1401 fnon-call-exceptions
1402 Common Report Var(flag_non_call_exceptions) Optimization
1403 Support synchronous non-call exceptions
1406 Common Report Var(flag_omit_frame_pointer) Optimization
1407 When possible do not generate stack frames
1409 foptimize-register-move
1410 Common Report Var(flag_regmove) Optimization
1411 Do the full register move optimization pass
1413 foptimize-sibling-calls
1414 Common Report Var(flag_optimize_sibling_calls) Optimization
1415 Optimize sibling and tail recursive calls
1418 Common Report Var(flag_partial_inlining)
1419 Perform partial inlining
1422 Common Report Var(pre_ipa_mem_report)
1423 Report on memory allocation before interprocedural optimization
1425 fpost-ipa-mem-report
1426 Common Report Var(post_ipa_mem_report)
1427 Report on memory allocation before interprocedural optimization
1430 Common Report Var(flag_pack_struct) Optimization
1431 Pack structure members together without holes
1434 Common RejectNegative Joined UInteger Optimization
1435 -fpack-struct=<number> Set initial maximum structure member alignment
1438 Common Report Var(flag_pcc_struct_return,1) Init(DEFAULT_PCC_STRUCT_RETURN)
1439 Return small aggregates in memory, not registers
1442 Common Report Var(flag_peel_loops) Optimization
1443 Perform loop peeling
1446 Common Report Var(flag_no_peephole,0) Optimization
1447 Enable machine specific peephole optimizations
1450 Common Report Var(flag_peephole2) Optimization
1451 Enable an RTL peephole pass before sched2
1454 Common Report Var(flag_pic,2)
1455 Generate position-independent code if possible (large mode)
1458 Common Report Var(flag_pie,2)
1459 Generate position-independent code for executables if possible (large mode)
1462 Common Report Var(flag_pic,1)
1463 Generate position-independent code if possible (small mode)
1466 Common Report Var(flag_pie,1)
1467 Generate position-independent code for executables if possible (small mode)
1470 Common Joined RejectNegative Var(common_deferred_options) Defer
1471 Specify a plugin to load
1474 Common Joined RejectNegative Var(common_deferred_options) Defer
1475 -fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>
1477 fpredictive-commoning
1478 Common Report Var(flag_predictive_commoning) Optimization
1479 Run predictive commoning optimization.
1481 fprefetch-loop-arrays
1482 Common Report Var(flag_prefetch_loop_arrays) Init(-1) Optimization
1483 Generate prefetch instructions, if available, for arrays in loops
1486 Common Report Var(profile_flag)
1487 Enable basic program profiling code
1490 Common Report Var(profile_arc_flag)
1491 Insert arc-based program profiling code
1494 Common Joined RejectNegative Var(profile_data_prefix)
1495 Set the top-level directory for storing the profile data.
1496 The default is 'pwd'.
1499 Common Report Var(flag_profile_correction)
1500 Enable correction of flow inconsistent profile data input
1504 Enable common options for generating profile info for profile feedback directed optimizations
1507 Common Joined RejectNegative
1508 Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=
1511 Common Var(flag_profile_use)
1512 Enable common options for performing profile feedback directed optimizations
1515 Common Joined RejectNegative
1516 Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=
1519 Common Report Var(flag_profile_values)
1520 Insert code to profile values of expressions
1523 Common Var(common_deferred_options) Defer
1526 Common Joined RejectNegative Var(common_deferred_options) Defer
1527 -frandom-seed=<string> Make compile reproducible using <string>
1529 ; This switch causes the command line that was used to create an
1530 ; object file to be recorded into the object file. The exact format
1531 ; of this recording is target and binary file format dependent.
1532 ; It is related to the -fverbose-asm switch, but that switch only
1533 ; records information in the assembler output file as comments, so
1534 ; they never reach the object file.
1535 frecord-gcc-switches
1536 Common Report Var(flag_record_gcc_switches)
1537 Record gcc command line switches in the object file.
1540 Common Report Var(flag_pcc_struct_return,0) Optimization
1541 Return small aggregates in registers
1544 Common Report Var(flag_regmove) Optimization
1545 Enables a register move optimization
1548 Common Report Var(flag_rename_registers) Init(2) Optimization
1549 Perform a register renaming optimization pass
1552 Common Report Var(flag_reorder_blocks) Optimization
1553 Reorder basic blocks to improve code placement
1555 freorder-blocks-and-partition
1556 Common Report Var(flag_reorder_blocks_and_partition) Optimization
1557 Reorder basic blocks and partition into hot and cold sections
1560 Common Report Var(flag_reorder_functions) Optimization
1561 Reorder functions to improve code placement
1563 frerun-cse-after-loop
1564 Common Report Var(flag_rerun_cse_after_loop) Optimization
1565 Add a common subexpression elimination pass after loop optimizations
1569 Does nothing. Preserved for backward compatibility.
1572 Common Report Var(flag_rounding_math) Optimization
1573 Disable optimizations that assume default FP rounding behavior
1576 Common Report Var(flag_schedule_interblock) Init(1) Optimization
1577 Enable scheduling across basic blocks
1580 Common Report Var(flag_sched_pressure) Init(0) Optimization
1581 Enable register pressure sensitive insn scheduling
1584 Common Report Var(flag_schedule_speculative) Init(1) Optimization
1585 Allow speculative motion of non-loads
1588 Common Report Var(flag_schedule_speculative_load) Optimization
1589 Allow speculative motion of some loads
1591 fsched-spec-load-dangerous
1592 Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
1593 Allow speculative motion of more loads
1596 Common RejectNegative Joined UInteger Var(sched_verbose_param)
1597 -fsched-verbose=<number> Set the verbosity level of the scheduler
1599 fsched2-use-superblocks
1600 Common Report Var(flag_sched2_use_superblocks) Optimization
1601 If scheduling post reload, do superblock scheduling
1605 Does nothing. Preserved for backward compatibility.
1608 Common Report Var(flag_schedule_insns) Optimization
1609 Reschedule instructions before register allocation
1612 Common Report Var(flag_schedule_insns_after_reload) Optimization
1613 Reschedule instructions after register allocation
1615 ; This flag should be on when a target implements non-trivial
1616 ; scheduling hooks, maybe saving some information for its own sake.
1617 ; On IA64, for example, this is used for correct bundling.
1618 fselective-scheduling
1619 Common Report Var(flag_selective_scheduling) Optimization
1620 Schedule instructions using selective scheduling algorithm
1622 fselective-scheduling2
1623 Common Report Var(flag_selective_scheduling2) Optimization
1624 Run selective scheduling after reload
1626 fsel-sched-pipelining
1627 Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
1628 Perform software pipelining of inner loops during selective scheduling
1630 fsel-sched-pipelining-outer-loops
1631 Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
1632 Perform software pipelining of outer loops during selective scheduling
1634 fsel-sched-reschedule-pipelined
1635 Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
1636 Reschedule pipelined regions without pipelining
1638 ; sched_stalled_insns means that insns can be moved prematurely from the queue
1639 ; of stalled insns into the ready list.
1640 fsched-stalled-insns
1641 Common Report Var(flag_sched_stalled_insns) Optimization UInteger
1642 Allow premature scheduling of queued insns
1644 fsched-stalled-insns=
1645 Common RejectNegative Joined UInteger
1646 -fsched-stalled-insns=<number> Set number of queued insns that can be prematurely scheduled
1648 ; sched_stalled_insns_dep controls how many recently scheduled cycles will
1649 ; be examined for a dependency on a stalled insn that is candidate for
1650 ; premature removal from the queue of stalled insns into the ready list (has
1651 ; an effect only if the flag 'sched_stalled_insns' is set).
1652 fsched-stalled-insns-dep
1653 Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
1654 Set dependence distance checking in premature scheduling of queued insns
1656 fsched-stalled-insns-dep=
1657 Common RejectNegative Joined UInteger
1658 -fsched-stalled-insns-dep=<number> Set dependence distance checking in premature scheduling of queued insns
1660 fsched-group-heuristic
1661 Common Report Var(flag_sched_group_heuristic) Init(1) Optimization
1662 Enable the group heuristic in the scheduler
1664 fsched-critical-path-heuristic
1665 Common Report Var(flag_sched_critical_path_heuristic) Init(1) Optimization
1666 Enable the critical path heuristic in the scheduler
1668 fsched-spec-insn-heuristic
1669 Common Report Var(flag_sched_spec_insn_heuristic) Init(1) Optimization
1670 Enable the speculative instruction heuristic in the scheduler
1672 fsched-rank-heuristic
1673 Common Report Var(flag_sched_rank_heuristic) Init(1) Optimization
1674 Enable the rank heuristic in the scheduler
1676 fsched-last-insn-heuristic
1677 Common Report Var(flag_sched_last_insn_heuristic) Init(1) Optimization
1678 Enable the last instruction heuristic in the scheduler
1680 fsched-dep-count-heuristic
1681 Common Report Var(flag_sched_dep_count_heuristic) Init(1) Optimization
1682 Enable the dependent count heuristic in the scheduler
1685 Common Report Var(flag_section_anchors) Optimization
1686 Access data in the same section from shared anchor points
1690 Does nothing. Preserved for backward compatibility.
1693 Common Report Var(flag_zee) Init(0)
1694 Eliminate redundant zero extensions on targets that support implicit extensions.
1697 Common Report Var(flag_show_column) Init(1)
1698 Show column numbers in diagnostics, when available. Default on
1701 Common Report Var(flag_signaling_nans) Optimization
1702 Disable optimizations observable by IEEE signaling NaNs
1705 Common Report Var(flag_signed_zeros) Init(1) Optimization
1706 Disable floating point optimizations that ignore the IEEE signedness of zero
1708 fsingle-precision-constant
1709 Common Report Var(flag_single_precision_constant) Optimization
1710 Convert floating point constants to single precision constants
1712 fsplit-ivs-in-unroller
1713 Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
1714 Split lifetimes of induction variables when loops are unrolled
1717 Common Report Var(flag_split_stack) Init(-1)
1718 Generate discontiguous stack frames
1721 Common Report Var(flag_split_wide_types) Optimization
1722 Split wide types into independent registers
1724 fvariable-expansion-in-unroller
1725 Common Report Var(flag_variable_expansion_in_unroller) Optimization
1726 Apply variable expansion when loops are unrolled
1729 Common Report RejectNegative Joined
1730 -fstack-check=[no|generic|specific] Insert stack checking code into the program
1733 Common Alias(fstack-check=, specific, no)
1734 Insert stack checking code into the program. Same as -fstack-check=specific
1737 Common Var(common_deferred_options) Defer
1739 fstack-limit-register=
1740 Common RejectNegative Joined Var(common_deferred_options) Defer
1741 -fstack-limit-register=<register> Trap if the stack goes past <register>
1743 fstack-limit-symbol=
1744 Common RejectNegative Joined Var(common_deferred_options) Defer
1745 -fstack-limit-symbol=<name> Trap if the stack goes past symbol <name>
1748 Common Report Var(flag_stack_protect, 1)
1749 Use propolice as a stack protection method
1751 fstack-protector-all
1752 Common Report RejectNegative Var(flag_stack_protect, 2)
1753 Use a stack protection method for every function
1756 Common RejectNegative Var(flag_stack_usage)
1757 Output stack usage information on a per-function basis
1761 Does nothing. Preserved for backward compatibility.
1763 ; Nonzero if we should do (language-dependent) alias analysis.
1764 ; Typically, this analysis will assume that expressions of certain
1765 ; types do not alias expressions of certain other types. Only used
1766 ; if alias analysis (in general) is enabled.
1768 Common Report Var(flag_strict_aliasing) Optimization
1769 Assume strict aliasing rules apply
1772 Common Report Var(flag_strict_overflow)
1773 Treat signed overflow as undefined
1776 Common Report Var(flag_syntax_only)
1777 Check for syntax errors, then stop
1780 Common Report Var(flag_test_coverage)
1781 Create data files needed by \"gcov\"
1784 Common Report Var(flag_thread_jumps) Optimization
1785 Perform jump threading optimizations
1788 Common Report Var(time_report)
1789 Report the time taken by each compiler pass
1792 Common Joined RejectNegative Enum(tls_model) Var(flag_tls_default) Init(TLS_MODEL_GLOBAL_DYNAMIC)
1793 -ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec] Set the default thread-local storage code generation model
1796 Name(tls_model) Type(enum tls_model) UnknownError(unknown TLS model %qs)
1799 Enum(tls_model) String(global-dynamic) Value(TLS_MODEL_GLOBAL_DYNAMIC)
1802 Enum(tls_model) String(local-dynamic) Value(TLS_MODEL_LOCAL_DYNAMIC)
1805 Enum(tls_model) String(initial-exec) Value(TLS_MODEL_INITIAL_EXEC)
1808 Enum(tls_model) String(local-exec) Value(TLS_MODEL_LOCAL_EXEC)
1811 Common Report Var(flag_toplevel_reorder) Init(2) Optimization
1812 Reorder top level functions, variables, and asms
1815 Common Report Var(flag_tracer)
1816 Perform superblock formation via tail duplication
1818 ; Zero means that floating-point math operations cannot generate a
1819 ; (user-visible) trap. This is the case, for example, in nonstop
1820 ; IEEE 754 arithmetic.
1822 Common Report Var(flag_trapping_math) Init(1) Optimization
1823 Assume floating-point operations can trap
1826 Common Report Var(flag_trapv) Optimization
1827 Trap for signed overflow in addition, subtraction and multiplication
1830 Common Report Var(flag_tree_ccp) Optimization
1831 Enable SSA-CCP optimization on trees
1834 Common Report Var(flag_tree_bit_ccp) Optimization
1835 Enable SSA-BIT-CCP optimization on trees
1839 Does nothing. Preserved for backward compatibility.
1842 Common Report Var(flag_tree_ch) Optimization
1843 Enable loop header copying on trees
1846 Common Report Var(flag_tree_copyrename) Optimization
1847 Replace SSA temporaries with better names in copies
1850 Common Report Var(flag_tree_copy_prop) Optimization
1851 Enable copy propagation on trees
1853 ftree-store-copy-prop
1855 Does nothing. Preserved for backward compatibility.
1858 Common Report Var(flag_tree_cselim) Init(2) Optimization
1859 Transform condition stores into unconditional ones
1861 ftree-switch-conversion
1862 Common Report Var(flag_tree_switch_conversion) Optimization
1863 Perform conversions of switch initializations.
1866 Common Report Var(flag_tree_dce) Optimization
1867 Enable SSA dead code elimination optimization on trees
1869 ftree-dominator-opts
1870 Common Report Var(flag_tree_dom) Optimization
1871 Enable dominator optimizations
1874 Common Report Var(flag_tree_dse) Optimization
1875 Enable dead store elimination
1878 Common Report Var(flag_tree_forwprop) Init(1) Optimization
1879 Enable forward propagation on trees
1882 Common Report Var(flag_tree_fre) Optimization
1883 Enable Full Redundancy Elimination (FRE) on trees
1885 ftree-loop-distribution
1886 Common Report Var(flag_tree_loop_distribution) Optimization
1887 Enable loop distribution on trees
1889 ftree-loop-distribute-patterns
1890 Common Report Var(flag_tree_loop_distribute_patterns) Optimization
1891 Enable loop distribution for patterns transformed into a library call
1894 Common Report Var(flag_tree_loop_im) Init(1) Optimization
1895 Enable loop invariant motion on trees
1898 Common Report Var(flag_tree_loop_linear) Optimization
1899 Enable linear loop transforms on trees
1902 Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
1903 Create canonical induction variables in loops
1906 Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
1907 Enable loop optimizations on tree level
1909 ftree-parallelize-loops=
1910 Common Report Joined RejectNegative UInteger Var(flag_tree_parallelize_loops) Init(1)
1911 Enable automatic parallelization of loops
1914 Common Report Var(flag_tree_phiprop) Init(1) Optimization
1915 Enable hoisting loads from conditional pointers.
1918 Common Report Var(flag_tree_pre) Optimization
1919 Enable SSA-PRE optimization on trees
1922 Common Report Var(flag_tree_pta) Init(1) Optimization
1923 Perform function-local points-to analysis on trees.
1926 Common Report Var(flag_tree_reassoc) Init(1) Optimization
1927 Enable reassociation on tree level
1931 Does nothing. Preserved for backward compatibility.
1934 Common Report Var(flag_tree_sink) Optimization
1935 Enable SSA code sinking on trees
1938 Common Report Var(flag_tree_sra) Optimization
1939 Perform scalar replacement of aggregates
1942 Common Report Var(flag_tree_ter) Optimization
1943 Replace temporary expressions in the SSA->normal pass
1946 Common Report Var(flag_tree_live_range_split) Optimization
1947 Perform live range splitting during the SSA->normal pass
1950 Common Report Var(flag_tree_vrp) Init(0) Optimization
1951 Perform Value Range Propagation on trees
1954 Common Report Var(flag_unit_at_a_time) Init(1) Optimization
1955 Compile whole compilation unit at a time
1958 Common Report Var(flag_unroll_loops) Optimization
1959 Perform loop unrolling when iteration count is known
1962 Common Report Var(flag_unroll_all_loops) Optimization
1963 Perform loop unrolling for all loops
1965 ; Nonzero means that loop optimizer may assume that the induction variables
1966 ; that control loops do not overflow and that the loops with nontrivial
1967 ; exit condition are not infinite
1968 funsafe-loop-optimizations
1969 Common Report Var(flag_unsafe_loop_optimizations) Optimization
1970 Allow loop optimizations to assume that the loops behave in normal way
1973 Common Report Var(flag_associative_math)
1974 Allow optimization for floating-point arithmetic which may change the
1975 result of the operation due to rounding.
1978 Common Report Var(flag_reciprocal_math)
1979 Same as -fassociative-math for expressions which include division.
1981 ; Nonzero means that unsafe floating-point math optimizations are allowed
1982 ; for the sake of speed. IEEE compliance is not guaranteed, and operations
1983 ; are allowed to assume that their arguments and results are "normal"
1984 ; (e.g., nonnegative for SQRT).
1985 funsafe-math-optimizations
1986 Common Report Var(flag_unsafe_math_optimizations) Optimization
1987 Allow math optimizations that may violate IEEE or ISO standards
1990 Common Report Var(flag_unswitch_loops) Optimization
1991 Perform loop unswitching
1994 Common Report Var(flag_unwind_tables) Optimization
1995 Just generate unwind tables for exception handling
2000 ; Positive if we should track variables, negative if we should run
2001 ; the var-tracking pass only to discard debug annotations, zero if
2002 ; we're not to run it. When flag_var_tracking == 2 (AUTODETECT_VALUE) it
2003 ; will be set according to optimize, debug_info_level and debug_hooks
2004 ; in process_options ().
2006 Common Report Var(flag_var_tracking) Init(2) Optimization
2007 Perform variable tracking
2009 ; Positive if we should track variables at assignments, negative if
2010 ; we should run the var-tracking pass only to discard debug
2011 ; annotations. When flag_var_tracking_assignments ==
2012 ; AUTODETECT_VALUE it will be set according to flag_var_tracking.
2013 fvar-tracking-assignments
2014 Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
2015 Perform variable tracking by annotating assignments
2017 ; Nonzero if we should toggle flag_var_tracking_assignments after
2018 ; processing options and computing its default. */
2019 fvar-tracking-assignments-toggle
2020 Common Report Var(flag_var_tracking_assignments_toggle) Optimization
2021 Toggle -fvar-tracking-assignments
2023 fvar-tracking-uninit
2024 Common Report Var(flag_var_tracking_uninit) Optimization
2025 Perform variable tracking and also tag variables that are uninitialized
2028 Common Report Var(flag_tree_vectorize) Optimization
2029 Enable loop vectorization on trees
2032 Common Report Var(flag_tree_slp_vectorize) Init(2) Optimization
2033 Enable basic block vectorization (SLP) on trees
2036 Common Report Var(flag_vect_cost_model) Optimization
2037 Enable use of cost model in vectorization
2039 ftree-vect-loop-version
2040 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
2041 Enable loop versioning when doing loop vectorization on trees
2043 ftree-vectorizer-verbose=
2044 Common RejectNegative Joined UInteger
2045 -ftree-vectorizer-verbose=<number> Set the verbosity level of the vectorizer
2048 Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
2049 Enable copy propagation of scalar-evolution information.
2051 ; -fverbose-asm causes extra commentary information to be produced in
2052 ; the generated assembly code (to make it more readable). This option
2053 ; is generally only of use to those who actually need to read the
2054 ; generated assembly code (perhaps while debugging the compiler itself).
2055 ; -fno-verbose-asm, the default, causes the extra information
2056 ; to not be added and is useful when comparing two assembler files.
2058 Common Report Var(flag_verbose_asm)
2059 Add extra commentary to assembler output
2062 Common Joined RejectNegative Enum(symbol_visibility) Var(default_visibility) Init(VISIBILITY_DEFAULT)
2063 -fvisibility=[default|internal|hidden|protected] Set the default symbol visibility
2066 Name(symbol_visibility) Type(enum symbol_visibility) UnknownError(unrecognized visibility value %qs)
2069 Enum(symbol_visibility) String(default) Value(VISIBILITY_DEFAULT)
2072 Enum(symbol_visibility) String(internal) Value(VISIBILITY_INTERNAL)
2075 Enum(symbol_visibility) String(hidden) Value(VISIBILITY_HIDDEN)
2078 Enum(symbol_visibility) String(protected) Value(VISIBILITY_PROTECTED)
2081 Common Report Var(flag_value_profile_transformations) Optimization
2082 Use expression value profiles in optimizations
2085 Common Report Var(flag_web) Init(2) Optimization
2086 Construct webs and split unrelated uses of single variable
2088 ftree-builtin-call-dce
2089 Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
2090 Enable conditional dead code elimination for builtin calls
2093 Common Report Var(flag_whole_program) Init(0) Optimization
2094 Perform whole program optimizations
2097 Common Report Var(flag_wrapv) Optimization
2098 Assume signed arithmetic overflow wraps around
2100 fzero-initialized-in-bss
2101 Common Report Var(flag_zero_initialized_in_bss) Init(1)
2102 Put zero initialized data in the bss section
2105 Common JoinedOrMissing
2106 Generate debug information in default format
2109 Common JoinedOrMissing Negative(gdwarf-)
2110 Generate debug information in COFF format
2113 Common Joined UInteger Var(dwarf_version) Init(2) Negative(gstabs)
2114 Generate debug information in DWARF v2 (or later) format
2117 Common JoinedOrMissing
2118 Generate debug information in default extended format
2121 Common JoinedOrMissing Negative(gstabs+)
2122 Generate debug information in STABS format
2125 Common JoinedOrMissing Negative(gvms)
2126 Generate debug information in extended STABS format
2129 Common RejectNegative Var(dwarf_strict,0) Init(-1)
2130 Emit DWARF additions beyond selected version
2133 Common Report RejectNegative Var(dwarf_strict,1)
2134 Don't emit DWARF additions beyond selected version
2137 Common Report Var(flag_gtoggle)
2138 Toggle debug information generation
2141 Common JoinedOrMissing Negative(gxcoff)
2142 Generate debug information in VMS format
2145 Common JoinedOrMissing Negative(gxcoff+)
2146 Generate debug information in XCOFF format
2149 Common JoinedOrMissing Negative(gcoff)
2150 Generate debug information in extended XCOFF format
2153 Driver Joined Separate
2156 Common Joined Var(plugindir_string) Init(0)
2157 -iplugindir=<dir> Set <dir> to be the default plugin directory
2160 Driver Joined Separate
2165 no-canonical-prefixes
2175 Common Driver Joined Separate Var(asm_file_name) MissingArgError(missing filename after %qs)
2176 -o <file> Place output into <file>
2179 Common Var(profile_flag)
2180 Enable function profiling
2183 Driver Var(pass_exit_codes)
2186 Common Var(pedantic)
2187 Issue warnings needed for strict compliance to the standard
2190 Common Var(flag_pedantic_errors)
2191 Like -pedantic but issue them as errors
2197 Driver Var(use_pipes)
2200 Driver JoinedOrMissing Var(print_file_name)
2202 print-libgcc-file-name
2205 print-multi-directory
2206 Driver Var(print_multi_directory)
2209 Driver Var(print_multi_lib)
2211 print-multi-os-directory
2212 Driver Var(print_multi_os_directory)
2215 Driver JoinedOrMissing Var(print_prog_name)
2218 Driver Var(print_search_dirs)
2221 Driver Var(print_sysroot)
2223 print-sysroot-headers-suffix
2224 Driver Var(print_sysroot_headers_suffix)
2227 Common Var(quiet_flag) RejectDriver
2228 Do not display functions compiled or elapsed time
2246 Driver Var(report_times)
2249 Driver JoinedOrMissing
2252 Driver Joined Separate
2256 ; C option, but driver must not handle as "-u ndef".
2259 Common Driver Var(verbose_flag)
2260 Enable verbose output
2263 Common Var(version_flag) RejectDriver
2264 Display the compiler's version
2267 Common Var(inhibit_warnings)
2271 Driver Separate Var(wrapper_string)
2274 Driver Joined Separate
2277 Common RejectNegative Negative(pie)
2278 Create a shared library
2284 Driver Separate Alias(specs=)
2297 ; Documented for Fortran, but always accepted by driver.
2304 ; Documented for Go, but always accepted by driver.
2310 Common RejectNegative Negative(shared)
2311 Create a position independent executable
2314 Driver Joined Separate
2316 ; This comment is to ensure we retain the blank line above.